In vivo and in vitro effect of progesterone on the growth of some mouse and human tumours

The effect of progesterone on the growth of tumours of different morphological and cytokinetic characteristics and origin has been investigated, such as mammary aplastic carcinoma, Ehrlich ascitic and solid tumour, fibrosarcoma, melanoma B-16, myeloid leukaemia and three cell lines, HeLa, HEp-2 and L929. The administration of progesterone has been proved to stimulate the growth of aplastic carcinoma of the breast in vivo. Directly implemented into cell culture of the same tumour it increased the incorporation of 3H-thymidine into DNA. In HeLa and HEp-2 cell cultures progesterone stimulated the population growth of these cells. However, progesterone has shown no effect at all on the growth of fibrosarcoma, melanoma, Ehrlich tumour, myeloid leukaemia and L929 cells, fibroblasts of C3H mice.